This invention relates to surface spreaders for applying particulate material to the surface of freshly-poured concrete, and in particular to an apparatus in combination with the surface spreader for accommodating and avoiding the interference of a column in line with an end of the surface spreader.
With the advent of automatic equipment for tamping and smoothing concrete, concrete is often laid in long, continuous ribbons of a particular width. Several ribbons of concrete may be poured adjacent one another over successive periods of time in order to complete a building floor or other similar surface.
After a ribbon of concrete is freshly laid, it is often desirable to add floating hardeners to the surface of the concrete before the concrete begins to cure. While, in the past, hardeners have been added by hand, hand-casting of hardeners normally leads to very imprecise dispersion of the hardeners across the concrete surface. Thus, various devices have been designed to span the width of a ribbon of freshly-poured concrete and dispense hardeners in a strip fashion across the concrete from a hopper designed to traverse above the concrete and dispense the hardening materials evenly across the concrete.
One problem with such devices is that in a situation where a pole, a building column, or other such obstruction is encountered at the edge of the concrete, the surface spreader must be manually lifted and moved from one side of the obstruction to the other, often precluding use of the surface spreader to spread the curing material in a strip across the concrete adjacent to the obstruction. Thus, dispensing of curing material at this location must be by imprecise hand application. Also, since the surface spreading equipment can span widths of concrete up to 70 feet or more, the surface spreading equipment tends to be quite heavy and bypassing such an obstruction is extremely difficult due to the bulk and weight of the equipment.